diff --git a/prebuild.xml b/prebuild.xml
index 2e73445640..1efeaf5582 100644
--- a/prebuild.xml
+++ b/prebuild.xml
@@ -2574,6 +2574,7 @@
 
       <ReferencePath>../../../bin/</ReferencePath>
       <Reference name="System"/>
+      <Reference name="System.Xml"/>
       <Reference name="Nini.dll"/>
       <Reference name="log4net.dll"/>